Electric switch



IJan. 6, 1931. C, W, WQOD l 1,788,224

ELECTRIC SWITCH Filed March 7, 1925 2 Sheets-Sheet l 2/ F12' 76 Tocircuit Breaker- 'Inventor Chur-les Wood,

` His- -Atto-rwelgl.

C. W. WOOD ELECTRIC SWITCH Jan. 6, 1931.

2 Sheets-Sheet 2 Filed March 7, 1925 inventor'. Charles W Wood,

bg His ttorr'xeg.

45 y grammaticY representation;

Patented Jany, 1931 Y 'PArENr 'gon-1ct f CHARLES W. woonk orLoNDonnNeLANn,AssIeNonjgro GENERAL nLEeTnIG com- ,f rANY,Aconron-Arronor NEW vom:

I' EIlEcTnrc f SWITCH vApplication nled March i, 19425, Lseril'yrro.13,867; 'and 11i Great Braam March 14,' 192e My invention relates toelectric switches, particularly to highl ten-sion switches fand an objectof my invention is rthe .provision of improved means lfor preventinga person from obtaining access tothe live elements of such al switchwithout vlfirst actuating another switch. torender dead the vcircuit ofthe first' switch.

Inaccordancefwith the embodiment of my loinvention disclosedherein Iemploy ,oney or:

more oil switches which are enclosed in chainbers having doors which areadapted to be locked closed by means of a key. In circuit 'with theoilswitchisan 'isolating switch and A a lock actuatedby the same key isprovidedy for locking it in -openfcircuit position.v The key cannot beremoved from the lock of the isolating switch without first" moving thisswitch to open lcircuit position .and locking it' in that position afterwhichthe key'may be.

Vapplied tothe lockv'controlling' the oilswitch chamber.V This latterlock,v moreover; is so `constructed that the key isv retained therein aslong as 'the door remainsopen to any ex-` tentso that itycannotfberemoved'while the door vis open and be applied to theisolating switch lock. n y My inventionwill be better understood fromthe ollowing'description taken in con- 39 nection with the accompanyingdrawing, and

its vscope will be pointed out in the appended# Figure 1 showsa partofthe mechanism involving my invention for operating an isog5 latingswitch having Va key controlled lock a'ttached'thereto;` Fig. 2'is adetail thereof;

Fig. 3 is a top view ofasliding chamber door having a lock adapted toreceivethe key fit Vting the isolating'switchlock; Fig.4 is a view '40of the 'door taken onthe line 4-#4 of 3;

' Figs. 5 and 6 are views similar tofF-igs. Sande respectively,` showingya modification gFig. 7 shows a further modiicationyFigs-S vand 9 showdetails of-.Figf 7 and `In Fig. 10 I have illustratedadiagr'ammaticmanneronlyanisolating switch 4 and an oil switch 5connectedin series to a line '6. `Itisto be understood that theseswitches vmay @o be 4of any wellknown `form and thatfaseCQnd Fig. 10l-isyadiaf S A* i "dicatedby thelbroken line'28 against theVcurved,"portionofthe vupper link 25, thus isolating yswitch lmayr bearranged the other side of the oil switch if vdesired..` By

way of e'XampleI have shown the isolating switch as operated `througha'crank 7 and alink 8.71 While the operating mechanism ofthe oil switchis not shown,` a tripping movable contact. Referring vnowfto Figs. 1 and2 the link 8 is 4pivotally" connected to the arm 11 'of the .hub`r 12which is Vmountedtor rotation on'the shaft 13 carried by brackets A14:.The brackets '14 are secured to the base 15 by bolts 16, and the wholemay be fixed in to koperate the lisolating switch.V IYo `ensurethatjtheisolatin switchjshall not be'opened untilthecircuitf reaker withwhich it is associated has iirst beenf'tripped, a shutterlS,V :operableb-y a handle 19, is mounted on the disc 22 for rotation about ythe shaft18 and is arranged normally to cover, ,or 'partly toV cover;l theopening of the hole 17. Operativeyly connectedto the disc 22 and therebyto the shutter 18 is a link 21, the other end of which is arranged toeifectthe'tripping ofthe circuitlbreaker in any suitable way when thelink is actuated by rotationr of theshutter 18 to a" predeterminedposition. On thej disc 22 are securedstop-pins 23. Fixed with `respecttothe basel is fabracket 24 to which. are

r'pivoted la pair of links "25. suitably shaped on their adjacent sidesto rest against aslee've26 on the Vshaft'l 'and 'also to bearagainst'the stopfpins"123, The links :25 are4 biased to- -wards leachother `by means` of a spring 27.

"VVithgthisarrangement, Awhen the shutter 18Lis rotated cleckwiise,(Figsl, 2) the disc 22 `is rotated yand:t'herewith the stoppt-pins 23,the

'means` therefor'is shown diagrammatically p comprisinga rod 9 engaginganotch 101 in the uppelble. Of'WhiCh moves along the curve inforcing itout into the position shown by broken lines against the'biasing effectorspring 27 sition under the influence of the spring 27. Aspring-controlled clamping device, having an arm 29 pivoted at 30 andadapted to engage with a cooperating catch or catches (not shown) on thedisc 22 is provided for latching the shutter in an operated position,for example, when it has been rotated clear of the opening of hole 17.Pressure on the control surface 3l of the clamping device effects therelease of the shutter. Y f7 f witlidrawable from the lock only when they locking lever thereof is in a predetermined key 36 can be withdrawn.that the keyA cannot be turned unless the hole position, that is,locked.V Such an arrangement might be obtained, for example with anykeyhole lock provided that the rotation of the key in the lock werelimited to an angle of less than 360. Cperable bythe moving element ofthe vlock is a shaft'37 to which is secured tlielocking lever38 having aforked end which engages with the stud 39. The stud is fixed to the bolt41 and in the hub 12 there is provided a hole 42 adapted to accommodatethe end ofthe-bolt 41 when the isolating switch lias'bcen moved into itsfull open-circuit position. y

The operation of this arrangement is as follows: When the. isolatingswitch is closed (and also the Circuit-breaker withfwhich the isolatingswitch is associated) the parts are in the position shown and the key istrapped into the lock. In order to obtain the key, it is necessary firstto rotate t-he handle 19in a clockwise direction sufficiently for theshutter 18 to uncover the opening of the hole 17, or, in fact, until thedisc 22 is engaged b v the lever 29V of the spring-controlled clampingdevice. This rotation immediatelyefiects the tripping of thecircuit-breaker through the link 21, and it is then safe to open theisolating switch, which can be done by inserting an implement in thehole 17 whereby leverage can be applied to rotate the hub 12 until thecenter line of the hole 17 coincides. with the broken line 32. Theisolating switch is now fully open and the holel 42 has moved intoalignment with the bolt 41. The arrangement isnow in a position for thekey 36 to be turned to rotate the shaft 37 and thereby to shoot the bolt4l intor the hole 42, thus locking the isolating switch open. When thishas been done the It should be noted 42 is aligned with the bolt`41v, asvfoi all `other positions of the lhole 42 the bolt Y41 just bears.against the surface of the hub l2. iWhen the key 36has beenwithdrawnitis available for insertion in one ofthe locks of thel chamberdooi'shereinafter described.` y

Referring now to Figs. 3 and 4, there is shownla part' of a sliding door43 adapted to breakers or other apparatus. When the door is lockedin'closed position, the lool-:ing lever 45 secured to and operable bythe shaft 37 of the lock 35, which is secured externally to the door, isarranged to bear against the plate .47 secured internally of the chamberto oneof the .walls 44. When the key 36 is inserted in the lock 35 andthe key and lock are so a-iranged that the key can only be inserted inor withdrawn from the lock when the locking lever thereof is in lockedposition) the locking lever 45 can be rotated into the position shown bybroken lines, in which position, it'will be noticed, the top of theplate 47 is just clear of the lower edge of the block 43 on the locking.lever 45 and the door can therefore be withdrawn. A roller-cam 49 fixedinternally ofthe chamber to one of the sides 44 is adapted to engagewith the vcam lever 51 pivoted at 52 to the door. As the door slidesout, the inclined surface 53 of the cam lever L51 bears against theroller-cam 49 and causes the lever 5l to rise to the position shown bybroken lines, a bracket plate 54 guiding it. The cam lever 51 hassecured to it a latch lever 55, adapted, when iii-raised position, tobear against the inclined surface 56 of the locking lever 45, thusretaining the same in its unlocked position.

It will be obvious from the foregoing that, once the lock isunlocked andthe door is moved into open position, the key is positively trapped in`this lock until such time as the door has again been shut and the keyturned to lock it closed.

.In Figs. 5 and 6 a portion of a cover 57 isr e hinged, as at 53, to oneof the side walls 44.

On this wall there is fixed a bracket 59 having a proyecting cam portion61 adapted to engage with a cam 62 on the camlever 63 which is pivotedat 64 to a bracket 65 secured Y ,externally to the door 57. When thedoor is closed and locked the end 66 of the locking lever 45 mounted onthe shaft 37 engages against the uptuined end 67 of the plate 68 securedto the other wall 44, thus preventing the door from being opened. Whenthe key 36 is inserted in the lock 35, the locking lever 45 can'berotated by means of the key to the position shown by broken lines, whenits end 66 is just clear of the upturned end 67 of the plate 68,' andthe doorv can, therefore, be swung open, 'The swinging open "of the doorcauses the cani lever 63 to rotate 'anti-clockwise about its pivot 64,due to the engagement of the cams 61, 62 andl this movementof the "'f"cam lever 63 is transmitted to a latchlever or rod 69 carried bybrackets 71 on the door causing the end 7 2 thereof to engage with acooperating portion7 3 on the locking lever to retain the same in itsunlockedposition.` The 5 compression spring 7,4 bearing 'against one lofthe brackets 71 and against the sleeve 7 5 secured to the rod 69v'isprovided for returning the rod to its off position when the door isagain closed. Y V

In Fig. 7 there are shown anumber of doors 7 6 hinged to walls lMaandcovering the front of a number of chambers arranged sidei by-sidebetween the walls. VIn normal conditions a bar 77, hinged for'inovementabout' the pivots 78 by links 79, lies close across the tops of thedoors, w-liereby they are prevented from being opened'.

1 ered by the doors 7 6. .Only when allthese locks are unlocked can theliandle86 be operated to raise-the locking bar 81 and there- 'by toraise the bai' 77 into the position shown by the broken lines, .when itis just clear of the upper ends of the doors76,l So soon as any or allof the doors are open, the bar 77 `Willlie on the top thereof and willtherefore be lprevented from moving into its lower position. The locks35 may be arranged as shown in Figs. 8 and 9. The bar 8l passes througheach lock framel 85 and is provided with slots 87 adapted when the locksare locked to be engaged by the cylindrical locking members SSoperableby the square shafts 37. Each member 88 is provided with a slot y89which is arrangedto be raligned with the bar 81 when the key 36 has beeninserted in the lock ,35 and turned throughl approximately 600, thuspermitting the bar 81 to be moved, provided that the other locks areunlocked. As soon as all the locks have been unlocked and the bar 8lmoved upwardly, the full width of the bar 8l will occupy the slots 89 ofthe locking membersr88 ofeach of the I locks 35 and thereby preventtheirrespective keys from being turned, which cannot in fact be effecteduntil all the doors 76 have again been closed, whereby the bar 77 andthe bar 81 can be moved'into their lower positions. v

o It should be understood that, as it is common for each circuit breakerto be associated f with two or more isolating switches, the locks y maybe: duplicated or.triplicated, there *being p one lock and itsassociated vparts foreach on the doors and the'trapping arrangementsisolating switch. c

IVhile I -have described certain embodiment-s,of'my'invention, I do not4wish, to be limited `to thenpartic'ular forms' shown and described asit will be apparent that many.v

A locking bai 81 adapted to pass through the lock-frames modificationstherein may be made without` departing from the scope of my invention asset forth in the appended claims. 4

W'hat I claim as new and desire to secure by Letters Patent of theUnitedStates, is

`l. In combination, an isolating switch operating mechanism, a key'actuated lock for securing said mechanism in open circuit position, achamber having a door adapted to enclose amain switch in series with theisolating switch, a lock for said door, saidmechanisin lock and `saiddoor lock being con-y structed to be actuated by the same key andpositively to prevent the removal therefrom of VVsaid key respectivelywhen the isolating switch mechanism is in closed circuit position andwhen the chamber doorfis not closed.

2. Incombination, an isolating switch op- Y erating" mechanism, akey-actuated lock for securing the mechanism in open circuit position,said key beingremovable Afrom the lock only when the switch is locked inopen circuit position, achamber havingfa door adapt-- ed to enclosearmain switch in series'with the f isolating switch, a lock'for securingsaidodoor in closed position, said door lock being operable by said keyand being constructed to Y prevent removal of the key when the lock isin unlocked position,`and means for positivelyy preventing movementfofsaid door lock to locking position when the door .is not closed.

3. In a. system comprising an isolating switch and a main switch inseries therewith',

a. rotatable operating member for'the isolatn ing switch having anopening therein adapted .to receive an actuating rod, arotatable shutteryadapted'in one kposition to extend over Vsaid opening and a connectionbetween said shutter and said main switch whereby the latter ris,ltripped lopen whenthe shutter is movedv 'from the kposition coveringsaid opening.

LA chamber adapted to enclose av switch comprising a door, a keyactuated lock thereon, said lock being constructed to Vpermit'removal ofthe key when the lock is in locking position and to prevent removal ofthe key whenl the lock is in its unlockedposition, and meansnonreleasable while the door is not closed for preventing movement ofthe lock to locking position. o V

5-` A chamber adapted toenclose a switch comprising a door, akey-actuated lock therefor,said lock ybeing constructed to'permit theremoval of thekey when the lock is in locking position and 'to preventthe removal of the key whenfthe lock is .in unlocked position and.

means automatically 'operated .by movement of the door from its,closedp'osition for positively preventing movement ofthe lock tolocking position.

In witness whereof, I have hereunto setmy y ima this 19a day ofFebruary; i925.

CHARLES wvwoo'D.

